A year and a half after two Sudanese military factions staged a joint coup against Sudan’s transitional government, war broke out between the factions. Attempts by regional and international actors to arrange a cessation of hostilities between the warring parties have failed. The United Nations Integrated Transition Assistance Mission in Sudan (UNITAMS) was dissolved in early 2024, unable to fulfil its mandate of advancing Sudan’s transition to democracy. UNITAMS could have been better equipped and endowed with a stronger and more realistic mandate for dealing with a contested transition. Arguably, however, it could not have prevented two armies that had conflicting interests and the resources to go to war from doing so. UNITAMS’s record is in line with an apparent historical truth of international relations: only major powers motivated to use their political and economic leverage decisively can change the calculations of imminent combatants.